Brake or stop mechanism



Feb. 19, 1957 E. J. HIRVONEN BRAKE 0R STOP MECHANISM Original Filed Oct;7, 1950 2 Sheets-Sheet 1 4r romvsv 'Feb. 19, 1957 E. J. HlRVONE-N BRAKE0R STOP MECHANISM Original Filed Oct. 7, 1950 2 Sheets-Sheet 2 R ON MEWm .H z m m H flm m RB E flZ/// All V/ m%4///4 4 m United States Patent2,781,672 BRAKE OR STOP MECHANISM Eric J. Hirvonen, Worcester, Mass,assignor to Leland- Giiford Company, Worcester, Mass., a corporation ofMassachusetts Original application October 7, 1950, Serial No. 183,002,

new Patent No. 2,647,407, dated August 4, 1953. Divided and thisapplication June 26, 1953, Serial No. 364,381

2 Claims. (Cl. 74531) This invention is a division of my priorapplication Serial No. 189,002 filed October 7, 1950, now Patent No.2,647,407, and relates in general to new and improved constructions formachine tool spindles and feed means therefor, having particularreference to those spindles which are fed or reciprocated by hydraulicpower, and including driven spindles for drill presses.

An object of the invention resides in the provision of a new andimproved safety locking means for the spindle, and including aconstruction whereby the spindle auto matically becomes locked at oneextreme limit thereof, not usually within the ordinary range ofreciprocation; the lock or latching means whereby this result isobtained being such as to require force to overcome, i. e., to unlockthe spindle and allow it to again come into action, the locking actionbeing easy and requiring little force, the unlocking action beingdifiicult and requiring considerable force.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings, in which Fig. 1 isa View partly in section through a spindle illustrating the presentinvention;

Fig. 2 is a sectional view on line 2-2 of Fig. 1;

Fig. 3 is an enlarged partial view in vertical section;

Fig. 4 is an enlarged section on the line 4-4 of Fig. 3; and a Fig. 5 isa section illustrating the invention.

This invention is herein illustrated as applied to a hydraulic drillingmachine but is not limited to such use or to this machine, and theinvention is capable of use wherever needed or desired but particularlyin the field of machine tool feeds.

A main housing is illustrated in part at and this housing is normallymounted on a standard as will be clear to those skilled in the art. Thehousing 10 supports all of the mechanism described herein and it is seenthat the drill spindle 12 herein as shown vertical, but, of course, itis understood that it may be horizontal or at any angle.

The housing 10 supports a motor 14 for the purpose of rotating thespindle and this motor may be supported in any way desired. Motor 14drives a pulley 16 through the intermediary of belts 18 in the usualmanner. This motor also drives a pulley 20 which is used to operate apump generally indicated at 22 for providing the hydraulic powerrequired for reciprocating the spindle during its fast travel, feed,reverse, etc. The spindle 12 is elongated and as shown in Fig. 1 it isat its uppermost position, i. e., fully retracted. The spindle 12 has achuck 24 at its lower end, and the greater length thereof is providedwith splines 26 which continue on to the upper end of the spindleindicated at 28.

These splines 26 longitudinally engage complementary interior keyways orthe like at 30 in a sleeve 32 which extends upwardly to bearings 34whereby it is held rotatably but is prevented against axial movement.The sleeve 32 continues upwardly at 36 where it is provided with thepulley 16 so that it is seen the spindle is rotated by the sleeve 32 andvet is axially adjustable in and out 2,781 ,672 Patented Feb. 19, 1957or up and down relative thereto, Sleeve 32 terminates splines as at 46so as to hold non-rotatably but axially sliding thereto a sleeve 48, thelatter having a rack 50 for adjustable engagement by a pinion 52rotatable by a hand crank 54. The sleeve 48 carries the bearing housingor head 58 thereon at the lower end thereof and thus it is seen that thehead is adjustable for the length of splines 46 relative to the drivingsleeve 32.

The sleeve 48 is non-rotatable but mounts a bearing rotatably supportingthe spindle 12 adjacent the lower portion thereof. The spindle 12 andthe bearing housing or head 58 are adjustable with sleeve 48 butrelative to an exterior sleeve 60 which, however, reciprocates thespindle, being normally clamped to sleeve 48 by a split collar clampingdevice 62 on ahead 63.

Sleeve 60 is secured to a piston 64 as at 66 and this piston, of course,reciprocates under influence of the hydraulic pump according to a valveand control system not herein illustrated. As clearly shown in Figs. 1and 3 the cylinder Wall is on the interior of sleeve 42 but the cylinderitself is annular and the inner wall is on sleeve 40, the spindle anddriving sleeve 32 being contained centrally thereof.

The head 63 is provided with a boss 68 on which is mounted a post 79,said post having a notch 72 cooperating with a ball 74 in a housing 76and backed up by a spring 78 in a channel 80. Said channel is at aparticular angle by means of which the post easily forces the ball 74reversely in channel 80 on the up stroke of the spindle, but once theball has been pushed aside and drops back into notch 72, the entireweight of the spindle and associated parts is easily held. This devicerequires considerable force exerted downwardly, to cause the ball toretract to release the post and become unlocked. In other words, theball is easily forced backwardly in its channel by an upward thrust ofpost 70 in the bore 82, but it is not easily thrust back in the channelby a downward thrust once the ball is seated in notch 72.

Having thus described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed, otherwise than asset forth in the claims, but what I claim is:

1. A reciprocatory member having an advance and a retractive stroke andmeans to latch the member at the end of the retractive stroke comprisinga movable element in a channel at an angle to the line of reciprocation,and means striking the element upon the member reaching the end of thestroke and pushing the element rearwardly in the channel, a recess inthe striking means receiving the element while still in the channel,resilient means urging the element towards the recess, the angle of thechannel being such as to cause relatively easy reception of the elementin the notch but difficult ejection thereof to allow a re-advance strokeof the member.

2. The member of claim 1 wherein the channel inclines outwardly and inthe direction of the motion of the member on the retractive stroke.

References Cited in the file of this patent UNITED STATES PATENTS2,202,217 Mallony May 28, 1940

